Effectiveness of a Cognitive and Behavioral Treatment Program in People With Idiopathic Environmental Intolerance (IEI)

Introduction:

A percentage of the population report various, nonspecific somatic and cognitive symptoms (e.g., headaches, nausea, fatigue, difficulty concentrating...) that they causally attribute to agents in their environments (chemicals, electromagnetic fields, windmills..). This condition is called Idiopathic Environmental Intolerance (IEI). It is proposed that the attribution of symptoms to an environmental agent, and the associated negative expectations is what drives symptom experience. We hypothesize that this, alongside other cognitive biases, are involved in the emergence and maintenance of symptoms. Treatment models have been developed, but no cognitive behavioral therapy was tested on IEI patients.

The planned study aims to investigate the feasibility and efficacy of a cognitive behavioral treatment online program, in ameliorating quality of life in a French population of patients suffering from IEI.

Methods and analysis:

This parallel two-armed, randomized controlled trial, evaluates an 8-week guided intervention against a wait-list control group. It is a hybrid intervention that will include web-based consecutive modules based on disorder-specific cognitive behavioral therapy (CBT) as well as general transdiagnostic principles . Guidance will be provided by trained psychologists with weekly supportive feedback.

As part of the "BELIEF" project, the present study aims to recruit n=82 patients indicating symptom attributed to factors in the environment. Assessments will take place at baseline and after intervention completion (12 and 24 weeks after randomization). The primary outcome will be measured by the SF-12 scale for quality of life. Secondary outcomes include symptom perception, severity and distress, eco-anxiety, emotional processing, intolerance to uncertainty and associated mental disorders such as depression and anxiety. Consumption of healthcare services will also be measured.

Ethics and dissemination:

Ethics approval has been granted. Results from this study will be published in peer-reviewed journals and presented at international conferences.

Trial registration number: DRKS00014375

• The Somatic Symptom Disorder - B Criteria Scale [Time frame: T0; 3 Months ; 6 Months]
• Symptom Interpretation Questionnaire [Time frame: T0; 3 Months ; 6 Months]
• QEESI (Quick environnemental exposure and sensitivity inventory) [Time frame: T0; 3 Months ; 6 Months]
• 11-item Electromagnetic Field Sensitivity Scale [Time frame: T0; 3 Months ; 6 Months]
• Modern Health Worries Scale short (12-item) version [Time frame: T0; 3 Months ; 6 Months]
• Climate Change Anxiety Scale [Time frame: T0; 3 Months ; 6 Months]
• Hospital Anxiety and Depression scale [Time frame: T0; 3 Months ; 6 Months]
• Short version of the Intolerance of Uncertainty Scale [Time frame: T0; 3 Months ; 6 Months]
• Body Perception Questionnaire - Very Short Form [Time frame: T0; 3 Months ; 6 Months]
• Levels of Emotional Awareness Scale 10 item [Time frame: T0; 3 Months ; 6 Months]